Photoluminescence behavior of europium (III) complexes containing 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione ligand.

Three novel europium complexes with 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione (TNPD) and 2,2-dipyridine (Bipy) or 1,10-phenan-throline (Phen) were synthesized and confirmed by FT-IR, (1)H NMR, UV-vis absorption and elemental analysis. Photoluminescence behavior of complexes Eu(TNPD)3, Eu(TNPD)3·Bipy and Eu(TNPD)3·Phen were investigated in detail. Their emission spectra exhibited the characteristic emission bands that arise from the (5)D0→(7)FJ (J=0-4) transitions of the europium ion in solid state. Meanwhile, the results of their lifetime decay curves indicated that only one chemical environment existed around the europium ion. The intrinsic luminescence quantum efficiency (η) and the experimental intensity parameters (Ωt) of europium complexes were determined according to the emission spectra and luminescence decay curves in solid state. The complex Eu(TNPD)3·Phen showed much longer lifetime (τ) and higher luminescence quantum efficiency (η) than complexes Eu(TNPD)3 and Eu(TNPD)3·Bipy.